Just moozing

Before you can check your notes, you must make them…

Lenovo Ideapad S12

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I have a Lenovo Ideapad  S12 running Linux. It is a good laptop with 12.1″ screen, but in bad need of a reinstallation. This post is about my reinstallation efforts.

What works after reinstallation

Let’s start with what is working.

  • Default installation suffers from the random freeze phenomenon and the wireless card is supported from kernel 2.6.34, so I installed my custom kernel, and now it works.
  • Wireless works in PIO mode [Update: Issues surfaced later. See here]
  • X.org and XFCE is working well. Tap-to-click and ctrl+alt+backspace work out of the box. This was actually to be expected.
  • OpenGl and Mesa are working too.
  • Hard disk access is much faster with no sudden hard disk related freezes.
  • Bluetooth seems to be working too, but I’m not sure since I never use it

In conclusion; Linux runs fine on the laptop.

Motivation for reinstallation

I have had a lot of problems with this PC. Especially the wireless part has been giving me problems. It uses a broadcom BCM 4312 wireless interface that is only supported stating from kernel 2.6.33, and even then only with some issues. One of the issues is that hardware interrupts must be turned off and use PIO mode instead. So the PC uses a lot of processor power when copying a lot from the network.

The worst part is the hard disk or the hard disk controller. The first hard disk died on me, and it took forever to get it fixed. Before reinstallation, I had full encryption on the entire hard disk, but it seem that there are some sort of interrupt issue that makes it stall from time to time and the performance was terrible. Since the encryption used LVM, I could not just revert my decision on using encryption of not.The interrupt issues showed as a complete stall of the machine for 10-20 seconds with kcryptd flatlining at 100%, so I went for the simplest solution with root, /home/and /stuff in three distinct partition (not using LVM). Performance was so bad that I could not watch movies that I had on the hard disk – not something I expect from a new Atom 1.6 Ghz laptop.

Also, the after doing an upgrade at some point the tap-to-click of the touchpad stopped working. It relates to some configuration value changing from some internal value to SI units. I tried fixing it, but I failed, and tap-to-click has been non-functioning for some time now.

I have no idea why, but ctrl+backspace never did work on the old installation. It is not something you use a lot, but when you are playing with X.org configuration, you want it.

The concept of kernels oopses was new to me, but now I have seen it enough. I hope the kernel guys benefit from my sending tons of automated messages to them. Personally, I don’t quite understand the gory technical stuff that is sent to them, but the statistics on their site seem to be a good tool for prioritizing the debugging resources.

Installation notes

This is my notes and links that I have used in the reinstallation

  • Check the BIOS setting for the hard disk controller. Mine is set to compatability mode. the other option (AHCI mode) has given me a lot of problems.
  • Installation is done from a USB stick using Debain netinst. Go to the debian documentation here for links. This took a couple of hours. It was a default installation. Any package tweaking was left for later (see next point).
  • I decided to reinstall all packages that I had previously. I order to do so, I used the dpkg –get-selections and –set-selections, followed by apg-get dselect-upgrade. I read this for the commands.
  • For some reason Iceweasel did not get installed. Don’t know why. Other packages are also missing, I suspect that it relates to the repositories included in sources-list, since default installation only include main.
  • This PC suffers from random freezes. It shows itself when the mouse of keyboard are not in use, then the clock, downloads and other activities stop. Some sort of timing interrupt gets disabled when using dynamic ticks and then nothing happens. Adding [Update] idle=nomwait processor.max_state=1 as kernel parameter works – it is not ideal (but less extreme than nohz=off) and works against power saving, but my battery currently gives me 5+ hours, so it is not currently an issue.
  • Adobe flash is to be installed also. I look here and install it from the contrib repository. I have tried gnash, but I find is too slow.
  • I use Zim and I wanted a never version than the one in stable. So I changed /etc/apt/sources.list to include the testing repositories. I decided to use testing for this installation.
  • I compile my own 2.6.34 kernel. It is fairly easy (when you have done it before). Testing comes with 2.6.32, which does not support my Broadcom BCM4312, but hibernation, CPU frequency scaling and the other important features are working. See below for wireless.

The work to come is the usual tweaking and installation of add-ons of the utilities, but the base system is working fine.

Wireless notes

In the log (/var/log/syslog) there are some lines about missing firmware for the b43. It direct you to http://wireless.kernel.org.

$ lspci -nn | grep 4312
03:00.0 Network controller [0280]: Broadcom Corporation BCM4312 802.11b/g LP-PHY [14e4:4315] (rev 01)

and comparing it to the list, it clearly states that the card is supported from 2.6.33 but only in PIO mode.

Installing b43-fwcutter did not include an automatic download of the drivers and I followed the instruction from the section entitled You are using the b43 driver from linux-2.6.25 or newer. The driver is actually quite verbose and any issue is reported in the log in a human readable way. I found it easy to Google the keywords.

Updates: The kernel parameter uses was wrong, now corrected to processor.max_state=1.


Written by moozing

July 26, 2010 at 09:00

Posted in Tech

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  1. […] 30, 2010 by moozing Leave a Comment After reinstalling my PC, I boldly announced that it was working fine. I was wrong, the wireless connection starting having issues, and I ended […]

  2. […] As a pointer for the efficiency of 3D stuff I run glxgears. On the laptop I get around 60 fps and almost no CPU usage. To people used to look at glxgears values, it is ridiculously low and, yes, it is a cheap non-gamer laptop. […]

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